Hi,

2003 Civic, 175k miles, only Mobil 1 Full Synthetic at 6-7k intervals since first oil change.

About 5k miles ago, my oil light has been coming on at start up.

If I leave the car sitting for longer than say, 12 hours, WHen I then start it up, the oil light goes off immediately at startup, stays off for a second, flickers once for about a 1/4 of a second then remains off during operation.

Any idea what it could be?

mlobur

 

First mechanically check your pressure if you want to know for sure you don't have a engine failure. But sending unit maybe BAD. Or a loose wire at the sending unit. Just because you run Mobil 1 doesn't mean anything. Mobil 1 won't allow an engine to run longer or better than an other oil. As long as it is changed regularly it the important thing. I change my oil & filters in my fleet of vehicles every 5000 miles. As a rule I run dino oil Valvoline. But recently I got 7 cases of Quaker State for $1/qt, so until that is gone they get that. In 50 years of owning & driving vehicles I have never lost an engine because oil, type, brand, weight, cost, etc. I have well over a few million miles under me & vehicles I have driven & owned.

 

Of course, you have confirmed that the oil level is OK, right?

It could be that the check valve in your oil filter has gone bad, allowing the oil to drain out of it while the engine is off.

This will of course start a lively discussion of which oil filter is best...

 

Does the 03 have a filter that is upside down? That is the only time I ever saw that issue. I had a 72 Toyota Pickup & they had upside down oil filters. If you didn't use an OEM you faced that issue. But I haven't heard of that since with any quality filter. The only filter I won't run is a FRAM.
But one way to rule that out is buy an OEM Honda filter & see.
The other thing is if he is running a 0-20 or 5-20 wt oil. There has been a lot of debate in lubrication magazines about these new little weight, fuel efficient oils. DO THEY PROVIDE ENOUGH LUBRICATION. With 175,000 miles maybe not NOW.